I agree - I ordered a 1.75" UNI with the rubber boot for around $12 and it clamps right on to the extension piece that attaches to the carb (original rubber tube clamps to this). I think the foam UNIs without a rubber boot are a little cheaper but I have not used them to say how well they hold up.
http://www.unifilter.com/online%20ca...universal.html
U402 is the foam and UP4182 is the pod.
Also, if you have the original filter I have seen people tear off the paper leaving the screen underneath and wrap it with foam filter element and seal the sides. That's another option as well if you want to keep the original filter frame.